Quarterly report pursuant to Section 13 or 15(d)

Capital Structure - Additional Information (Detail)

Capital Structure - Additional Information (Detail) - USD ($)							1 Months Ended	9 Months Ended
	Sep. 30, 2016	Jul. 27, 2016	Nov. 02, 2015	Jun. 12, 2015	Jun. 11, 2015	Aug. 01, 2014	Jan. 31, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Jul. 31, 2014
Class of Stock [Line Items]
Common stock, shares authorized	100,000,000							100,000,000		100,000,000	100,000,000
Common stock, par value	$ 0.0001							$ 0.0001		$ 0.0001
Issuance costs allocated to warrants								$ 1,569,341
Proceeds from private placement								$ 35,000,000	$ 20,000,000
IPO, closing date								Aug. 01, 2014
Initial public offering, units description								Each unit consisted of one share of common stock, one Class A Warrant to purchase one share of common stock at an exercise price of $4.80 per share and one Class B Warrant to purchase one-half share of common stock at an exercise price of $4.00 per full share.
Net proceeds from initial public offering						$ 35,000,000
Proceeds from exercise of warrants								$ 16,000	$ 201,315
Common stock, voting rights								The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings.
Dividends declared or paid	$ 0
Private Placement [Member]
Class of Stock [Line Items]
Number of shares issued				4,728,128	4,728,128
Warrants to purchase shares of common stock	189,126			2,364,066	2,364,066			189,126
Net proceeds received				$ 18,300,000	$ 18,300,000
Warrant exercise price per share	$ 4.65			$ 8.00	$ 8.00			$ 4.65
Warrants expiration period				3 years
Proceeds from private placement				$ 20,000,000
Warrant expiration date								Jun. 11, 2020
Initial Public Offering [Member]
Class of Stock [Line Items]
Number of shares issued						6,880,333
Public offering price, per unit						$ 6.00
Common stock units issued upon exercise of option by underwriters						880,333
At the Market Equity Offering Program [Member] \| Maximum [Member] \| Cowen and Company, LLC [Member]
Class of Stock [Line Items]
Aggregate gross sales proceeds from common stock							$ 30,000,000
Follow-on Offering [Member]
Class of Stock [Line Items]
Number of shares issued		14,000,000
Warrants to purchase shares of common stock		14,000,000
Aggregate gross sales proceeds from common stock		$ 35,000,000
Net proceeds received		$ 32,000,000
Warrant exercise price per share		$ 3.00
Public offering price, per unit		$ 2.50
Follow-on Offering [Member] \| CMPO Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock		14,000,000
Warrant exercise price per share		$ 3.00
Warrant expiration term		5 years
Fair value of warrants		$ 18,601,228
Issuance costs allocated to warrants		$ 1,569,341
Class B Warrants [Member]
Class of Stock [Line Items]
Warrant expiration date								Nov. 02, 2015
Warrants exercised			4,812,328
Common stock shares issued upon exercise of warrants			2,406,164
Proceeds from exercise of warrants			$ 9,600,000
Unexercised warrants terminated			2,068,005
Class B Warrants [Member] \| Initial Public Offering [Member]
Class of Stock [Line Items]
Warrant exercise price per share						$ 4.00
Representative's Warrant [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock	206,410							206,410
Warrant exercise price per share	$ 7.50							$ 7.50
Warrant expiration date								Aug. 27, 2019
Class of warrant purchase percentage	3.00%							3.00%
Warrant exercisable period								180 days
Class A Warrants [Member] \| Initial Public Offering [Member]
Class of Stock [Line Items]
Warrant exercise price per share						$ 4.80